the pen that
Él escribió cartas con la pluma que le compré por su cumpleaños.
He wrote letters with the pen I bought him for his birthday.
La pluma que has cogido de la mesa es de Sara.
The pen you picked up from the table belongs to Sara.
La pluma que Sara me dio no es azul.
The pen Sara gave me is not blue.
Esta es la pluma que se me perdió ayer.
This is the pen I lost yesterday.
La pluma que estás sujetando ahora es mía.
The pen you're holding right now is mine.
La pluma que le di a Sara era roja.
The pen I gave Sara was red.
I use the pen you gave me.